HJ76
#include <stdio.h>
#include<stdlib.h>
int main() {
    int m = 0;
    while (scanf("%d", &m) != EOF) { // 注意 while 处理多个 case
        // 64 位输出请用 printf("%lld") to
        int* p = (int*)malloc(sizeof(int) * m);
        int n = m * (m + 1);
        int tmp = m;
        for (int i = 0; i < tmp; i++) {
            p[m - 1] = n - 1;
            n -= 2;
            m--;
        }
        for (int i = 0; i < tmp; i++) {
            if (i < tmp - 1)
                printf("%d+", p[i]);
            if (i == tmp - 1)
                printf("%d", p[i]);
        }
    }
    return 0;
}